11,860 research outputs found
Set-up effects of piles in sand tested in the centrifuge
The bearing capacity of piles increases over time. Research has shown that this is caused by an increase in shaft friction combined with a constant or only slightly increasing base capacity. Although there are some ideas on the mechanisms that play a role there is no quantitative model to describe this mechanism. From the literature the shaft friction seems to increase linearly with the logarithm of time. For piles in the field this is proven by load tests performed between 1 until approximately 1000 days after installation. Literature indicates that set-up as a function of time is also present minutes and hours after installation. This allows investigating the set-up mechanisms under controlled conditions in a centrifuge. Therefore two test series have been performed to investigate the set-up for a single pile and a pile group. This paper presents the relevant literature and describes the position of the tests in the on-going research program on piles in The Netherlands. Furthermore, the results will be described and discussed. Time dependency in bearing capacity in sand can be observed in the centrifuge tests, although it is not certain whether some of the increase has not been caused by other mechanisms. It appears that the testing conditions as well as the effects of installation of neighboring piles are of great importance on the time effects
In vitro and in vivo survival of mouse morulas and blastocysts following vitrification in 45% glycerol
The toxicity of cryoprotectant agents is one of the critical factors for the successful vitrification of mammalian embryos, which depends on the concentration, time and temperature of exposure to the cryoprotectant. Moreover, embryos from different species or stages of development have distinct levels of tolerance to cryoprotectant agents. This study aimed to evaluate the in vitro and in vivo survivals of mouse embryos after distinct times of exposure to two cryoprotectant concentrations prior to vitrification. In Experiment 1, compact morulas, blastocysts and expanded blastocysts were exposed to 10% glycerol for 10 min (group 1) or to 25% glycerol for 10, 5 and 2.5 min (groups 2, 3, and 4, respectively) prior to their exposure to the vitrification solution containing 45% glycerol for 1 min at 20°C before immersion in liquid nitrogen. Embryos were thawed in a water bath at 20°C for 20 sec, and the cryoprotectant was diluted in 1 M sucrose for 10 min. Then, embryos were morphologically evaluated following in vitro culture for 1 and 48 h. In vitro survivals of compact morulas and blastocysts were not affected by glycerol concentration and/or equilibration time prior to vitrification. However, expanded blastocysts demonstrated a lower survivability to vitrification. In Experiment 2, fresh and vitrified (according to procedures in group 1, Experiment 1) compact morulas and blastocysts were transferred to recipients following in vitro culture for 1 h at room temperature. Pregnancy rates, based on the proportion of viable fetuses, were similar between vitrified and fresh compact morulas (27% and 33%, respectively). However, vitrified blastocysts demonstrated a lower in vivo survival than controls (9% vs. 52%, respectively)
The Proctolin Gene and Biological Effects of Proctolin in the Blood-Feeding Bug, Rhodnius prolixus
We have reinvestigated the possible presence or absence of the pentapeptide proctolin in Rhodnius prolixus and report here the cloning of the proctolin cDNA. The transcript is expressed in the central nervous system (CNS) and some peripheral tissues. The proctolin prepropeptide encodes a single copy of proctolin along with a possible proctolin-precursor-associated peptide. We have biochemically identified proctolin in CNS extracts and shown its distribution using proctolin-like immunoreactivity. Immunostained processes are found on the salivary glands, female and male reproductive tissues, and heart and associated alary muscles. Proctolin-like immunoreactive bipolar neurons are found on the lateral margins of the common oviduct and bursa. Proctolin is biologically active on R. prolixus tissues, stimulating increases in contraction of anterior midgut and hindgut muscles, and increasing heartbeat frequency. Contrary to the previous suggestion that proctolin is absent from R. prolixus, proctolin is indeed present and biologically active in this medically important bug
COMPETÊNCIAS REQUERIDAS DOS DOCENTES DAS INSTITUIÇÕES DE ENSINO SUPERIOR, FRENTE ÀS TECNOLOGIAS DIGITAIS
Este trabalho teve como objetivo geral identificar a influência das TIC’s - Tecnologias da Informação e Comunicação, no processo ensino/aprendizagem nas Instituições de Ensino Superior, e apresentar as competências requeridas dos Docentes, considerando a velocidade do processamento da informação. A gestão por competência compreende que ensinar também é aprender, ou seja, é ir além de transmitir um só conhecimento, fruto de uma interpretação solidificada, onde o Docente é aquele que tudo sabe, enquanto o aluno é como uma tábua rasa, vazio de saberes, histórias e marcas. As novas tecnologias da informação e da comunicação transformam a maneiras de comunicar, trabalhar, decidir, pensar, inovar. Portanto, a educação no Ensino Superior deve utilizar-se das novas tecnologias para auxiliar no desenvolvimento do pensar crítico, bem como, na tomada de decisão sobre o que já está definido e qual a habilidade aplicada para facilitar o trabalho ou as relações sociais. No que tange as principais tecnologias utilizadas pelos Docentes nas IES, destacam-se a Intranet, Editores de textos, Ferramentas multimídias e softwares Educativos. Metodologicamente, quanto aos fins, a presente pesquisa classifica-se como estudo descritivo e aplicado. Quanto aos meios de investigação, pode ser classificada como pesquisa bibliográfica
CRIATIVIDADE COMO DIFERENCIAL NAS ORGANIZAÇÕES DE ENSINO SUPERIOR
Apesar das atividades operacionais do ser humano estarem sendo executadas por máquinas, existe, entretanto, uma capacidade essencial às organizações, que com certeza muito tempo levará para que as máquinas a substitua, a criatividade. Neste sentido, visualizando que as organizações são formadas por processos, sistemas, pessoas e tecnologias, existe a necessidade de investigar a criatividade e suas implicações no resultado como diferencial nas organizações. Abordamos nesse artigo, o processo de mudança vivenciado atualmente nas organizações de Ensino Superior onde a demanda não se resume apenas ao seu patrimônio físico,capitais financeiros, tecnológicos etc. Mas também, nas habilidades que permitam o desenvolvimento da criatividade, na capacidade intelectual das pessoas que nela atuam. É justamente no cérebro das pessoas que está a riqueza das organizações e a vantagem competitiva está no conhecimento. As organizações, portanto, precisam conhecer os fatores que influenciam a criatividade, proporcionando condições para o seu desenvolvimento, garantindo assim, vantagens competitivas. Atualmente, ainda não se pode considerar que exista uma compreensão total do processo criativo, ou resumir a criatividade a um simples conceito, pois a mesma manifesta-se de maneiras diferentes, motivo pelo qual, ainda hoje, gera controvérsias. A metodologia adotada neste trabalho foi a pesquisa bibliográfica em fontes secundárias
Fungiculture in termites is associated with a mycolytic gut bacterial community
ABSTRACT Termites forage on a range of substrates, and it has been suggested that diet shapes the composition and function of termite gut bacterial communities. Through comparative analyses of gut metagenomes in nine termite species with distinct diets, we characterize bacterial community compositions and use peptide-based functional annotation method to determine biomass-degrading enzymes and the bacterial taxa that encode them. We find that fungus-growing termite guts have relatively more fungal cell wall-degrading enzyme genes, while wood-feeding termite gut communities have relatively more plant cell wall-degrading enzyme genes. Interestingly, wood-feeding termite gut bacterial genes code for abundant chitinolytic enzymes, suggesting that fungal biomass within the decaying wood likely contributes to gut bacterial or termite host nutrition. Across diets, the dominant biomass-degrading enzymes are predominantly coded for by the most abundant bacterial taxa, suggesting tight links between diet and gut community composition, with the most marked difference being the communities coding for the mycolytic capacity of the fungus-growing termite gut. IMPORTANCE Understanding functional capacities of gut microbiomes is important to improve our understanding of symbiotic associations. Here, we use peptide-based functional annotation to show that the gut microbiomes of fungus-farming termites code for a wealth of enzymes that likely target the fungal diet the termites eat. Comparisons to other termites showed that fungus-growing termite guts have relatively more fungal cell wall-degrading enzyme genes, whereas wood-feeding termite gut communities have relatively more plant cell wall-degrading enzyme genes. Across termites with different diets, the dominant biomass-degrading enzymes are predominantly coded for by the most abundant bacterial taxa, suggesting tight links between diet and gut community compositions
Leak detection using cepstrum of cross-correlation of transient pressure wave signals
A new leak detection method is proposed here which is based on the cepstrum of the cross-correlation of the pressure signals from two transducers. Computational simulations of leaks with different properties, size, position and shape, in a straight pipe and a T-Junction network were studied. The proposed method was successful in estimating leakages and the pipeline features with a high precision. For the results with a straight pipe, this method is considerably more accurate than using the cross-correlation leak detection method or the cepstrum method alone. However, the results obtained by cepstrum and cepstrum of cross-correlation for the T-Junction case were quite accurate, while cepstrum alone showed a slightly better precision
A UNIVERSIDADE CORPORATIVA COMO MEIO DE DESENVOLVIMENTO DA APRENDIZAGEM ORGANIZACIONAL: O CASO SEBRAE.
Este artigo objetiva descrever como os procedimentos que caracterizam a Universidade Corporativa SEBRAE estão alinhados às teorias abordadas na presente pesquisa, com base, principalmente, nos Sete Princípios de Sucesso de um Sistema de Educação Corporativa levantados por Eboli (2004). Além de se observar como a referida Universidade influencia no desenvolvimento do colaborador e contribui para a Aprendizagem Organizacional. O artigo é resultado de uma pesquisa de natureza aplicada, de abordagem qualitativa, descritiva, bibliográfica, documental e estudo de caso. Como resultado foi observado que a Universidade comtempla os princípios de sucesso, e colabora para a construção da Aprendizagem Organizacional do SEBRAE. Porém, consiste em um projeto de constante revisão, e que precisa se ajustar para continuar perpetuando se forma efetiva
Management of effluents and waste from pharmaceutical industry in Minas Gerais, Brazil
Today the management of solid waste and wastewater is a major concern for humanity. In the last decade, traces of pharmaceuticals have been reported in the water cycle and have raised concerns among regulators, water suppliers and the public regarding the potential risks to human health. This study evaluated solid waste management in the state of Minas Gerais and concluded that the main fate of hazardous waste has been incineration, while the non-hazardous waste has been recycled or sent to landfills. However, complaints to the Environmental Agency - FEAM have indicated that a significant number of companies just send their hazardous wastes to landfills or even to garbage dumps, thus highlighting the urgent need for adequate waste management in Minas Gerais. Most of the pharmaceutical companies in Minas Gerais use conventional wastewater treatment. Mass spectrometry with electrospray ionization (ESI-MS) showed that the treatment routes adopted by the two 2 selected pharmaceutical industries were not effective enough since residues and degradation products of antibiotics were detected. The physicochemical analysis of the effluents showed variability in their characteristics, which may influence their treatability. The degradation assay with Fenton's reagent stood out as a promising route in achieving a higher removal capacity compared to the conventional treatment. This study contributes to enhancing our knowledge of the management of wastewater as well as of solid waste from the pharmaceutical industry in Minas Gerais and points out the need for further research.Atualmente, a gestão de resíduos sólidos e águas residuais é uma grande preocupação para a humanidade. Na ultima década, a detecção de traços de medicamentos no ciclo da água tem sido reportada e tem gerado preocupação entre os agentes reguladores, fornecedores de água e público devido os riscos potenciais para a saúde humana. As empresas farmacêuticas, em Minas Gerais, aplicam tratamentos convencionais para as águas residuais e não há praticamente avaliação sobre a eficiência de remoção de resíduos de antibióticos. Este estudo avaliou a gestão de resíduos sólidos e concluiu que o destino principal foi, para o caso de resíduos perigosos, a incineração e, para os não perigosos, a reciclagem e o aterro sanitário. No entanto, denúncias apresentadas à Agência Ambiental - FEAM indicam que número significativo de empresas envia seus resíduos perigosos para aterros sanitários e até mesmo para lixões, ressaltando, assim, a necessidade urgente de adequada gestão dos resíduos gerados. A espectrometria de massas com ionização electrospray (ESI-MS) mostrou que a rota de tratamento convencional adotada por duas empresas do setor selecionadas não foi suficientemente eficaz, uma vez que resíduos e fragmentos de antibióticos foram detectados. Os resultados da caracterização físico-química de efluentes evidenciaram suas características variáveis, que podem influenciar a sua tratabilidade. O ensaio de degradação com o reagente Fenton destaca-se como caminho promissor para alcançar maior remoção. Este estudo contribuiu para elevar o nível de conhecimento no gerenciamento de águas residuais e resíduos sólidos da indústria farmacêutica no estado de Minas Gerais e evidenciou a necessidade de estudos mais detalhados
Growth of the Eucalyptus urograndis, Schizolobium parahyba var. amazonicum, Tectona grandis and Ochroma pyramidale on integration crop-livestock-forest systems in the Amazon Biome.
The objective of this study was to evaluate the growth in diameter and height eucalyptus (hybrid Eucalyptus urograndis), paricá (Schizolobium parahyba var. amazonicum), teak (Tectona grandis) and balsa tree (Ochroma pyramidale), seeking to supply information about the use of these species in crop-livestock-forest integration (ICLF) systems
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